The present invention relates to a wide-angle/telephotography convertible camera which can selectively perform either wide-angle photography or telephotography, and more particularly it relates to a device which generates an incorrect lens setting signal when a wide-angle/telephotography changeover member is not correctly set in the wide-angle position or the telephoto position.
Wide-angle/telephotography convertible cameras, which can selectively perform either wide-angle photography or telephotography, are widely known in the art. The wide-angle/telephotography convertible camera can be of one kind in which a conversion lens is disposed so as to move in or out of the optical train behind a main lens, or of another kind in which a wide-angle lens and a telephoto lens are juxtaposed and the path of the received light is switched by moving a mirror disposed in front of the film.
With wide-angle/telephotography convertible cameras of these kinds, the photographic image cannot be formed at a correct position on the film unless the wide-angle/telephotography changeover manipulable member for moving the conversion lens or the mirror is in the correct position. It is known in the art (for example, Japanese Patent Laid-open Publication No. 53-14931) that a cam mechanism moving in association with the positioning mechanism of a conversion lens can be provided so that when the lens is not correctly positioned, a red filter is inserted into the optical path of the viewfinder to give an indication of incorrect lens setting. However, cameras using such a mechanism have the problem that the structure is complicated and the manufacturing cost is high.